/***************************************************************************
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*****************************************************************************/


#include "common.h"

#include <arm_neon.h>

#define	N	"x0"	/* vector length */
#define	X	"x1"	/* "X" vector address */
#define	INC_X	"x2"	/* "X" stride */
#define	Y	"x3"	/* "Y" vector address */
#define	INC_Y	"x4"	/* "Y" stride */
#define J	"x5"	/* loop variable */

#define REG0	"xzr"
#define DOTF	"d0"
#define TMPX	"d16"
#define LD1VX	"{v16.d}[0]"
#define TMPY	"d24"
#define LD1VY	"{v24.d}[0]"
#define SZ	"8"

#if defined(SMP)
extern int blas_level1_thread_with_return_value(int mode, BLASLONG m, BLASLONG n,
	BLASLONG k, void *alpha, void *a, BLASLONG lda, void *b, BLASLONG ldb,
	void *c, BLASLONG ldc, int (*function)(), int nthreads);
#endif


static FLOAT ddot_compute(BLASLONG n, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y)
{
	FLOAT  dot = 0.0 ;

	if ( n < 0 )  return(dot);

	__asm__ __volatile__ (
	"	mov	"N", %[N_]			\n"
	"	mov	"X", %[X_]			\n"
	"	mov	"INC_X", %[INCX_]		\n"
	"	mov	"Y", %[Y_]			\n"
	"	mov	"INC_Y", %[INCY_]		\n"
	"	fmov	"DOTF", "REG0"			\n"
	"	fmov	d1, "REG0"			\n"
	"	fmov	d2, "REG0"			\n"
	"	fmov	d3, "REG0"			\n"
	"	fmov	d4, "REG0"			\n"
	"	fmov	d5, "REG0"			\n"
	"	fmov	d6, "REG0"			\n"
	"	fmov	d7, "REG0"			\n"

	"	cmp	"N", xzr			\n"
	"	ble	.Ldot_kernel_L999		\n"

	"	cmp	"INC_X", #1			\n"
	"	bne	.Ldot_kernel_S_BEGIN		\n"
	"	cmp	"INC_Y", #1			\n"
	"	bne	.Ldot_kernel_S_BEGIN		\n"

	".Ldot_kernel_F_BEGIN:				\n"
	"	asr	"J", "N", #5			\n"
	"	cmp	"J", xzr			\n"
	"	beq	.Ldot_kernel_F1			\n"

	"	.align 5				\n"
	".Ldot_kernel_F32:				\n"
	"	ldp	q16, q17, ["X"]			\n"
	"	ldp	q24, q25, ["Y"]			\n"
	"	ldp	q18, q19, ["X", #32]		\n"
	"	ldp	q26, q27, ["Y", #32]		\n"
	"	fmla	v0.2d, v16.2d, v24.2d		\n"
	"	fmla	v1.2d, v17.2d, v25.2d		\n"
	"	ldp	q20, q21, ["X", #64]		\n"
	"	ldp	q28, q29, ["Y", #64]		\n"
	"	fmla	v2.2d, v18.2d, v26.2d		\n"
	"	fmla	v3.2d, v19.2d, v27.2d		\n"
	"	ldp	q22, q23, ["X", #96]		\n"
	"	ldp	q30, q31, ["Y", #96]		\n"
	"	add	"Y", "Y", #128			\n"
	"	add	"X", "X", #128			\n"
	"	fmla	v4.2d, v20.2d, v28.2d		\n"
	"	fmla	v5.2d, v21.2d, v29.2d		\n"
	"	PRFM	PLDL1KEEP, ["X", #896]		\n"
	"	PRFM	PLDL1KEEP, ["Y", #896]		\n"
	"	PRFM	PLDL1KEEP, ["X", #896+64]	\n"
	"	PRFM	PLDL1KEEP, ["Y", #896+64]	\n"
	"	fmla	v6.2d, v22.2d, v30.2d		\n"
	"	fmla	v7.2d, v23.2d, v31.2d		\n"

	"	ldp	q16, q17, ["X"]			\n"
	"	ldp	q24, q25, ["Y"]			\n"
	"	ldp	q18, q19, ["X", #32]		\n"
	"	ldp	q26, q27, ["Y", #32]		\n"
	"	fmla	v0.2d, v16.2d, v24.2d		\n"
	"	fmla	v1.2d, v17.2d, v25.2d		\n"
	"	ldp	q20, q21, ["X", #64]		\n"
	"	ldp	q28, q29, ["Y", #64]		\n"
	"	fmla	v2.2d, v18.2d, v26.2d		\n"
	"	fmla	v3.2d, v19.2d, v27.2d		\n"
	"	ldp	q22, q23, ["X", #96]		\n"
	"	ldp	q30, q31, ["Y", #96]		\n"
	"	add	"Y", "Y", #128			\n"
	"	add	"X", "X", #128			\n"
	"	fmla	v4.2d, v20.2d, v28.2d		\n"
	"	fmla	v5.2d, v21.2d, v29.2d		\n"
	"	PRFM	PLDL1KEEP, ["X", #896]		\n"
	"	PRFM	PLDL1KEEP, ["Y", #896]		\n"
	"	PRFM	PLDL1KEEP, ["X", #896+64]	\n"
	"	PRFM	PLDL1KEEP, ["Y", #896+64]	\n"
	"	fmla	v6.2d, v22.2d, v30.2d		\n"
	"	fmla	v7.2d, v23.2d, v31.2d		\n"

	"	subs	"J", "J", #1			\n"
	"	bne	.Ldot_kernel_F32		\n"

	"	fadd	v0.2d, v0.2d, v1.2d		\n"
	"	fadd	v2.2d, v2.2d, v3.2d		\n"
	"	fadd	v4.2d, v4.2d, v5.2d		\n"
	"	fadd	v6.2d, v6.2d, v7.2d		\n"
	"	fadd	v0.2d, v0.2d, v2.2d		\n"
	"	fadd	v4.2d, v4.2d, v6.2d		\n"
	"	fadd	v0.2d, v0.2d, v4.2d		\n"
	"	faddp	"DOTF", v0.2d			\n"

	".Ldot_kernel_F1:				\n"
	"	ands	"J", "N", #31			\n"
	"	ble	.Ldot_kernel_L999		\n"

	".Ldot_kernel_F10:				\n"
	"	ldr	"TMPX", ["X"]			\n"
	"	ldr	"TMPY", ["Y"]			\n"
	"	add	"X", "X", #"SZ"			\n"
	"	add	"Y", "Y", #"SZ"			\n"
	"	fmadd	"DOTF", "TMPX", "TMPY", "DOTF"	\n"

	"	subs	"J", "J", #1			\n"
	"	bne	.Ldot_kernel_F10		\n"

	"	b	.Ldot_kernel_L999		\n"

	".Ldot_kernel_S_BEGIN:				\n"
	"	lsl	"INC_X", "INC_X", #3		\n"
	"	lsl	"INC_Y", "INC_Y", #3		\n"
	"	asr	"J", "N", #2			\n"
	"	cmp	"J", xzr			\n"
	"	ble	.Ldot_kernel_S1			\n"

	".Ldot_kernel_S4:				\n"
	"	ld1	"LD1VX", ["X"], "INC_X"		\n"
	"	ld1	"LD1VY", ["Y"], "INC_Y"		\n"
	"	fmadd	"DOTF", "TMPX", "TMPY", "DOTF"	\n"
	"	ld1	"LD1VX", ["X"], "INC_X"		\n"
	"	ld1	"LD1VY", ["Y"], "INC_Y"		\n"
	"	fmadd	"DOTF", "TMPX", "TMPY", "DOTF"	\n"
	"	ld1	"LD1VX", ["X"], "INC_X"		\n"
	"	ld1	"LD1VY", ["Y"], "INC_Y"		\n"
	"	fmadd	"DOTF", "TMPX", "TMPY", "DOTF"	\n"
	"	ld1	"LD1VX", ["X"], "INC_X"		\n"
	"	ld1	"LD1VY", ["Y"], "INC_Y"		\n"
	"	fmadd	"DOTF", "TMPX", "TMPY", "DOTF"	\n"
	"	subs	"J", "J", #1			\n"
	"	bne	.Ldot_kernel_S4			\n"

	".Ldot_kernel_S1:				\n"
	"	ands	"J", "N", #3			\n"
	"	ble	.Ldot_kernel_L999		\n"

	".Ldot_kernel_S10:				\n"
	"	ld1	"LD1VX", ["X"], "INC_X"		\n"
	"	ld1	"LD1VY", ["Y"], "INC_Y"		\n"
	"	fmadd	"DOTF", "TMPX", "TMPY", "DOTF"	\n"
	"	subs	"J", "J", #1			\n"
	"	bne	.Ldot_kernel_S10		\n"

	".Ldot_kernel_L999:				\n"
	"	fmov	%[DOT_], "DOTF"			\n"

	: [DOT_]  "=r" (dot)		//%0
	: [N_]    "r"  (n),		//%1
	  [X_]    "r"  (x),		//%2
	  [INCX_] "r"  (inc_x),		//%3
	  [Y_]    "r"  (y),		//%4
	  [INCY_] "r"  (inc_y)		//%5
	: "cc",
	  "memory",
	  "x0", "x1", "x2", "x3", "x4", "x5",
	  "d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7"
	);

	return(dot);
}

#if defined(SMP)
static int ddot_thread_function(BLASLONG n, BLASLONG dummy0,
	BLASLONG dummy1, FLOAT dummy2, FLOAT *x, BLASLONG inc_x, FLOAT *y,
	BLASLONG inc_y, FLOAT *result, BLASLONG dummy3)
{
	*result = ddot_compute(n, x, inc_x, y, inc_y);

	return 0;
}
#endif

FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y)
{
#if defined(SMP)
	int nthreads;
	FLOAT dummy_alpha;
#endif
	FLOAT dot = 0.0;

#if defined(SMP)
	nthreads = num_cpu_avail(1);

	if (inc_x == 0 || inc_y == 0)
		nthreads = 1;

	if (n <= 10000)
		nthreads = 1;

	if (nthreads == 1) {
		dot = ddot_compute(n, x, inc_x, y, inc_y);
	} else {
		int mode, i;
		char result[MAX_CPU_NUMBER * sizeof(double) * 2];
		FLOAT *ptr;

		mode = BLAS_DOUBLE  | BLAS_REAL;

		blas_level1_thread_with_return_value(mode, n, 0, 0, &dummy_alpha,
				   x, inc_x, y, inc_y, result, 0,
				   ( void *)ddot_thread_function, nthreads);

		ptr = (FLOAT *)result;
		for (i = 0; i < nthreads; i++) {
			dot = dot + (*ptr);
			ptr = (FLOAT *)(((char *)ptr) + sizeof(double) * 2);
		}
	}
#else
	dot = ddot_compute(n, x, inc_x, y, inc_y);
#endif

	return dot;
}